Toggle link jack with two



Oct. 3, 1950 A. NIEDERHAUSER 23,278

'roccuz LINK JACK WITH TWO LIFTING PHASES 2 Sheets-Sheet 1 Original Filed Aug 6, 1947 HIIIII:

Illl! ll Oct. 3, 1950 A. NI EDERHAU'SER 23,273

TOGGLE LINK JACK WITH TWO LIFTING PHASES Original Filed Aug. 6, 1947 2 Sheets-Sheet 2 venfor:

Reissued Oct. 3, 1950 TOGGLE LINK JACK WITH TWO LIFTENG PHASES Alfred Niederhauser, Salt Lake City, Utah Original No. 2,458,407, dated January 4, 1949, Se-

rial No. 766,811, August 6, 1947.

Application for reissue February 24, 1950, Serial No. 146,095. In Switzerland October 21, 1944 Section 1, Public Law 690, August 8, 1946 Patent'exp'ires October 21, 1964 Matter enclosed in heavy brackets appears in the original patent but forms no part of this reissue specification; matter printed in italics indicates the additions made by reissue 9 Claims.

The present invention refers to a lifting jackfor automobiles and othenloads, which has two lifting arms parallel to each other and connected together at their free ends by a tippable beam, the arms being jointed at their lower ends each to a threaded sleeve movable by a threaded spindle, and being pivotably connected by links to the frame of the lifting jack.

In known lifting jacks of this kind, lifting arms are arranged directed opposite to one another, their upper ends carrying a saddle for engaging on the load, and their lower ends being moved towards each other in order to raise the arms. Other known liftin jacks have only one lifting arm or a pair of lifting arms, to whose middle part links are attached, which are directed opposite to each other and swivelling on the frame of the lifting jack. With these jacks, in order that the power exerted may not be too great and injurious at the beginning of the lift of the lifting arms 1. e. in their lowest position, the lifting arms directed against each other or the lifting arms with their links must form a suitable angle at their connecting place, which makes it practically impossible to construct such jacks with the desired very low height and suitable for heavy loads.

On the other hand, the aim of the present invention is to create a very low lifting jack adaptable also for bi loads, in which jack the fulcrums of the levers are not unduly stressed in any position of the liftin arms.

The essential features of the invention can be ascertained from the following description and the corresponding drawings.

Fig. 1 shows a side view of the transportable lifting jack with the lifting arms in the lowest position, without driving motor, and

Fig. 2 the same in plan view.

Fig. 3 shows a side view of the lifting jack set 2 motor not shown in the drawing. on each threaded spindle 2 a threaded sleeve I (Fig. 2) is screwed, to one of which sleeves each lower end of a lifting arm 8 is pivotally connected. Opposite the two lever arms 8, a link 9 is arranged on each of their two sides, which link is held pivoted at its lower end on a pivot pin Ill fixed on the frame I. The upper ends of the links 9 are carried on the bar I I connecting the lifting arms 8. On each of the free ends of the liftin arms 8 a pivot pin I2 is arranged above their longitudinal middle axis, to which a lifting beam I3 is tippably arranged, bridging over these ends. These-ends of the lifting arms are also rigidly connected together by a cross bar I4, Whose middle part, as shown in Fig. 4 lies by means of rollers I5 on each of the shoe-shaped angle-levers I6 when the lifting arms 8 are in the lowest, horizontal position. Each of the two bellcranks or angle-levers I6 is pivoted by a pin I 6a to a pair of straps I! (Fig. 2) which are rigidly secured to the frame I. A link I8 (Fig. 4) is pivoted at one end to each bellcrank I6 by means of a pin I 82. some distance below pin Ifia and at the other end by pin IBb to a headpiece I9 movable in the frame. The headpiece I9 is firmly connected to a beam 20 which extends over the whole width of the rear part of the lifting jack frame I and is displaceably supported with its ends in the two profile irons I on both sides of the frame (Fig. 4). The two rear ends of the threaded spindles serving to drive the lifting device are formed as ready for service, with the lifting arms in the first lifting phase. a

Fig. 4 illustrates, on a larger scale, the mechanism for effecting the first lifting phase.

Fig. 5 is a diagrammatic representation of the position of the joint of a lifting arm, of its link and of the tippable beam.

The transportable lifting jack has a rectangular frame I formed of channel iron in which two parallel threaded spindles 2 are rotatably supported and axially displaceable through a certain distance. These spindles 2 are connected to each other through sprockets 3, 4 and chain 5, and are in synchronous rotational connection with a driving shaft 6 which can be coupled to a threaded pins and lead through bores in the headpiece I9 and the beam 20. Between each of the nuts 2i fixed on the spindle ends 2' and the beam 20, a ball bearing 22 is arranged which can withstand great pressures. In consequence of being supported axially displaceable in the frame I, the two spindles 2 at the beginning of their lifting drive recede, i. e., shift to the right as seen in Fig. 2, under the effect of the force acting on thesleeves 1 which is caused by the weight of the lifting member and any load on it. The beam 20 with its headpiece I9 is pulled to the right, as seen in Fig. 4, by nuts 2| on spindles 2, transmitting its motion through link I8 to the angle-lever I5, thus causing it to pivot up and so cause the arms 8 to be raised underneath the engaging places on the load. The first lifting mechanism bein'g s'iib'jedted to undiily great'radial pressures which would cause them to fail by shearing.

The axles of the joints of the li-fting mecha I nism, as diagrammatically illustrated in Fig. 5, are arranged so that, with the spindle axis 2 in horizontal position and the fever arma "-i'n' lowest position, the'fixed axis=l'on frameJ for the pivoting of the link Edies-"alppfoximately at the same height as the pivdt -axle 'l ofetheiliftlng arm 8 at the threaded sleeve of the spindle- 2, biit lower than the tipping axle l2 of the beam 13 which is located above the longitiidifrial fi'niddle axis at the free end of the lifting arm 8. There suit of this arrangement of the pivot axafiliich is'-also in accordance with theinvention, that inbeing'raised dr lowered the liftingb'ea'm l3 describes a vertical path, whereby in the case of heavy loads dangerods lateral displacements of them-are prevented. V v

By'the described-arrangement of the members "Whl'ChPIOdl-lCG the firstliftingrphase, by the man- -n'er in-which-the leversgrip under the crossbeam -of the lifting -arms, also with the desired flow build of -the--lifting jarzlh-whichrpresumes an'ini- -tia1 position with the lifting -members laid :togetherapproximatel-y, in-one planea slightrais- 'ing of-these member-sis obtained until-the formationmf a -suitable -tr-iangle'-" of forces --for 'the inirtialrmovementcaused-by the --thrust=efiect on one endcf -thelifting arms. In :addition, the-drive f-of-each of the two-spindles allocated tothe two flitting --arms by a common driving shaft gives a liftingmovement of-thelifting-beam the-same-in -each phase, in spite of the loading at the different posit-ionsof the beam being in practice-generally 'iunequal.

-For --drl-ving theshaft --5 a motor (not shown) erected onthe-frame i -is-inlmown manneripro- Wided with-"control members for automatically switching =-the motor off -when the highest and lowestpositions of -the lifting beam I3 are'reached. The l'ifting jack =ismade -transportableby the imembe'rs =23 *to-32, inclusive whose function I is apparerrtlfr'om Figs. 1 and 3. This-mechanism forms the subject matter 0f -my 'cepending aps'plieation Serial No. 766,812, filed August 6, 1947.

V What-I claim and desire to protectby=-Letters Patent is:

ls'A lifting flack comprising a frame, a "link spi'votally connectedat one end to 'said frame, edriven=means mounted in said frame for -movement toward and "away from said Epivotal :con- -nection,-"alifting arm pivoted -'at onea'end -to--said means and-at an intermediate'point to the-other end of =said link, thereby forminga toggle mechanism/which in lowesti position has-the three pivot points substantially inhorizontalalignment, and auxiliary means. independe tof said link operat-. Wil en-"said 'liftin'ghrm between its free and and its-pivotal connectionzbith said'li'nk fonlifting *t-he freeend-of said lifting-arm;sufiiciently-to -form a suitable'triang'le of'forcesfor the-lifting movement of said lifting arm produced by' sa-id -driven means.

-2.. A lifting jack comprising a frame; lifti-ng members including a lifting arm-slidablymou-nted atoneend in said=frame and a link pivoted at its respective ends tosaid frame andto saidliftingarm intermediate-its-ends, said members ininitial position lying approximately in a horizontal i-plane; means for moving said 'slidably mounted end of said lifting arm toward and away -from said link; andan auxiliary device-pperatinwon:

said lifting arm between its free end and its .471'ifiitlil 'iizmi'tecfion with sliid ili' ikF'for lifting the free end of said lifting arm from said initial position sufficiently to form a suitable triangle of :forces :for the lifting movement produced by movement of said means toward said link and for lowering the same to initial position on return il'iblflh fit.

;3.,A lifting.-jackcomprising a frame, a threaded spindle rotatably mounted in said frame and 11x) capable of=axial-displacement, a threaded sleeve -on saidfspmdie, a lifting arm pivoted at one end to said sleeve, a link pivoted at its respective ends wsaierrameand to said lifting arm intermediate its'e'ridsfanangle lever pivoted to said frame with one arm adapted to raise and lower the free end of said lifting arm respectively from and to an initial 'ipdsiti'on .an'd with the other arm opera- "'tiv'ly "dl'l'l'lelit d' With' Said Spin die for "movement when said spindle is agzially displaced, and means .for rotating saidspindle.

915. :lif-ting jjack "comprising a frame, two threaded's'pindles 'rotaltabiy mounted in "spaced paralll relation in said "frame and "capable of limited axial mo'venfent, "a threaded sleeve 'on each spindle,"twofparallel lifting arms connected together adjacent toth'eiffree ends by arbrossbar and each pivoted atthe. other endto one of said sleeves, links pivoted a'tith'ei'r "respective ends to saidfraniererndte from "Said "sleeves and to said lifting arms intermediate the ends "thereof, "an angle ilever pivoted "toifsai'd frame with *one "arm adapted "to engage saidbr'ossb'ar and "the other arm operativelyfcdrinectd withsaidspindles for movementwlien' they "are :axially f displaced, "and I means for ro'tatirfg lsaidsplndles.

v5. 'Aj-liftih'ggjack comprisin "a rectangular frame, abear'nfnovabl'y Tr'no'un'ted in said frame adjacent. to one end "thereof, two threadedspim dleslrdtatably' mounted in spaced parallel relam n in said frame at sneqena and insaid' beam at the lotheri'nd'and capable of axial'displacement i in a said frame, "a" nut on each "spindle en- .gagerble-fiithfsfifd beam, "athreadedsIeeVe on eachspindlezadjaenttdtheendmounted'in said frame, Ttwo 'Lparallel lifting arms "connected ''together adjacent 'to theiffreeends" by a "crossbar and each pivoted at the other end to oneof' said sleevesfillnksepivoted at tlfii'frespective ends to v sai d frame" remotelfro'm saidsleevs ahdtosaid litting arms intermediate "the ends'thereof, said lifting arms and links inth'e'lowestfpositionflying approximately in=one plane within 's'aidframe, two JJellcranks .-.pivoted 'to said .franle adjacent to said beam with oneiarm. adapted toeng'ag'e'said crossbar for an initial-phaseof'its upward move- =ment,--a"link-connecting the other arm of each bellcrank with said beam, and means 'for rotating said spindlesdnunisonwhereby theinitial force 'exerted by said sleeves displaces said spinidles axially -and throughsaid tnuts moves the beam and ibellcranks to raise the free end of said lif-tingsrm fer the initial. phase-of its upward movement and thereafter the force exerted by said sleeves'movesthetpivoted ends of said lift- -in'g arms in -said iframe and --completes the up ward movement of theefree ends thereof by togglea'ction'. 7

- liftmgjack asset forth inclaim -in=which a: lifting:beam-ispivoted totheireeencls of said 'lifting arms.

-7. .tyl-ifti-ng;jack-aisset= forthin claimfiin which said -'lifting beam -moves vertically.

8. lifting .ij-a'ek comprising a frame, two threaded spindles journaled in said 7 frame, a threaded sleeve on each spindle, a lifting arm pivoted at oneend to each of said sleeves, a beam pivoted to the other ends of said arms, links pivoted at one end to said frame and at the other end to said arms between said sleeve and beam pivots, all said pivots except said beam pivots lying substantially in a plane in said frame when the lifting arms are in lowest position, said beam pivots being above said plane, means for rotating said spindles, and auxiliary means to impart initial upward movement to said lifting arms from said lowest position upon rotation of said spindles.

9. A lifting jack adapted for lifting heavy loads high enough for a man to work conveniently thereunder comprising a low rectangular frame capable of resting directly over its entire area on a fiat supporting surface, a pair of lifting arms slidably mounted at one end in said frame, links pivoted at their respective ends to said frame and said lifting arms at a point intermediate the ends thereof, said links and lifting arms forming a toggle which in lowest position lies approximately in one plane in said frame, means for producing a thrust on the slidably mounted ends of said lifting arms, and means operating on at least one of said lifting arms between its free end and its pivotal connection with, said link for raising said lifting arms an initial distance sufficient to form a suitable triangle of forces for the initial movement caused by said thrust.

ALFRED NIEDERI-IAUSER.

REFERENCES CITED The following references are of record in the file of this patent or the original patent:

UNITED STATES PATENTS 

